Process of refining mineral oils



Patented Oct. 18, 1927.

PATENT OFFICE.

'THEODOB HELLTHALER, OF GRANSCHUTZ, GERMANY, ASSIGNOR TO THE FIRM: HUGOSTINTNES BIEBECK MONTAN UND dIaWERKE ART. (3138., OF HALLE-ON-THE-SAALE,

GERMANY.

PROCESS OF REFINING MINERAL OILS.

No Drawing. Application filed August 1, 1925, Serial No. 47,608, and inGermany December 3, 1924.

This invention relates to the process of refining mineral oils of everydescription. This process was hitherto generally carried out by treatingthe oils with sulphuric acid 6 whereby the basic substances, and suchwhich cause the formation of resins and asphalt are removed, but at thesame time a. number of undesired secondary reactions take place, whichfor a long time have been the object 10 of particular investigations.For instance, it is well known, that, besides acid resins, numerousoxidation products and sulfo compounds are formed, which, owing to theirgenerally rather viscous consistency contain considerable (puantities ofrefined products.

Furthermore y the subsequent inevitable washing process the oils areemulsified, thereby calusing the loss of considerable quantities o 01Many experiments have been made to substitute other chemical agents forsulphuric acid. Thus among other substances anhydrous tin tetrachloridehas been pro osed as a refining agent. However, on su jecting mineraloils to the action of this product under the conditions described in theliterature a more or less violent reaction with the roduction of heat isobserved which depen s upon the quantity of the unsaturated compoundspresent. Each added drop is at once enclosed in a dark, spongy resinousmass, whereby the refining agent is prevented from further action uponthe mineral oil. Therefore with this method a sufiiciently refined andclarified oil can only be obtained when employing considerablequantities of riialfining agents, and with very great loss of Now I havefound that these disadvantages are avoided by sub'ecting the mineraloils to tin tetrahalogeni s in a finely distributed or diluted 'form.This may be effected by the adsorption of the tin com ounds by suitablesoli finely distributed odies such as fullers earth, sllicate ofalumina, infusorial earth (fieselguhr), clay, activated carbon, sodaash, calcium carbonate and the like. Instead of solid diluents, 1i uidorganicsolvents not participating in' t e reaction may 60 also beemployed, such as chlorinated hydrocarbons, petroleum ether, benzin andthe like. When tin tetrahalogenids, for instance tin tetrachloride SnCl,in this form is made to act on mineral oils, the violent reactionbefewer quantities of the reagent will, sufiice,

the resinous or asphaltic masses simultaneously produced being adsorbedby the solid substrate or dissolved by the organic solvents.Furthermore, the employing of solid substrata has the advantage ofmanipulating such powdery substances more conveniently than theviolently fuming and corrosive tin tetrahalogenid. Of course solid andliquid dlluents may be used simultaneously.

With my improved method a subsequent distillation is not needed in mostcases. but refined products of light color and free from asphalt areimmediately obtained. It is advisable to follow up the treatment of theoils by a subsequent treatment with suitable basic substances suchasbleaching earth or the like, whereby at the same time the hydrochloricor other acid formed is neutralized, and the oils are further clarified.The tin employed may be easily recovered from the residue by knownmethods.

The process forming the object of the present invention may be employedfor refining mineral oils of every description, such as petroleum orpetroleum distillates, shale oil, or shale oil distillates, lignite tarprimary or low temperature distillation, tar or its distillates and thelike.

Ewamples.

(1) A dark, opaque dynamo oil showing s ecific gravity 0.906, viscosityat 20 C. 11.5 inglers scale), as-halt 0.1 p. ct., was treated underviolent stirring with 6 p. ct. by weight of a mixture consisting of 1art of tin tetrachlorid and 2 parts of earth, ltered and shaken with 5p. ct. of alkaline bleaching earth or water. A bright yellow lubricantwas obtained having the following properties: 20 C. 10.6 asphalt none.

(2) An as halt-like lubricating oil not well adapted or being refinedobtamedfrom Mexican raw oil showln'g specific gravity at 20 C. 0.948,viscosity at C. 9.1 E., as-

halt 0.2 p. ct., was treated with 12 p. ct. of its weight of a powderconsisting of equal parts of tin tetrachloride and aluminum c111- cate,and a refined product wholly free from asphalt and having the followingproperties neutral sgecific gravity 0.901, viscosity at mee ew m 4% .5E. halt none.

T oifl wee efi e yeHeW ,ee mi iend had an i m il ml the erimlpi'oduct.

i m minerel oils 1: '1 I v mtpe eeipimiedi Ii m lmh si' in treetin the"oils with finely dis-,

elogenids and thereafter meme eimxtetm with beeie blleecg earth.

3. The process of refining mineral 0ils c0nsieting in meeting the oilswith tin tetrahelogenids finely (iistributed in an, inert diluent andthereafter with basic bleaching i h f 1 1 i n tesfnimon W ereo riili msi suture.

'i i'ilil HELL%ER.

